Author + information
- Received February 19, 2013
- Revision received May 28, 2013
- Accepted June 13, 2013
- Published online October 1, 2013.
- Christian Bjurman, MD∗,
- Mårten Larsson, MD†,
- Per Johanson, MD, PhD‡,
- Max Petzold, PhD∗,
- Bertil Lindahl, MD, PhD§,
- Michael L.X. Fu, MD, PhD∗ and
- Ola Hammarsten, MD, PhD†∗ ()
- ∗Department of Medicine, Sahlgrenska University Hospital at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- †Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- ‡Department of Cardiology, Sahlgrenska University Hospital at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- §Department of Medical Sciences, Cardiology and Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden
- ↵∗Reprint requests and correspondence:
Dr. Ola Hammarsten, Department of Clinical Chemistry and Transfusion Medicine, Bruna Stråket 16, Sahlgrenska Academy at the University of Gothenburg, Gothenburg SE-413 45, Sweden.
Objectives The purpose of this study was to examine the extent of change in troponin T levels in patients with non–ST-segment elevation myocardial infarction (NSTEMI).
Background Changes in cardiac troponin T (cTnT) levels are required for the diagnosis of NSTEMI, according to the new universal definition of acute myocardial infarction. A relative change of 20% to 230% and an absolute change of 7 to 9 ng/l have been suggested as cutoff points.
Methods In a clinical setting, where a change in cTnT was not mandatory for the diagnosis of NSTEMI, serial samples of cTnT were measured with a high-sensitivity cTnT (hs-cTnT) assay, and 37 clinical parameters were evaluated in 1,178 patients with a final diagnosis of NSTEMI presenting <24 h after symptom onset.
Results After 6 h of observation, the relative change in the hs-cTnT level remained <20% in 26% and the absolute change <9 ng/l in 12% of the NSTEMI patients. A relative hs-cTnT change <20% was linked to higher long-term mortality across quartiles (p = 0.002) and in multivariate analyses (hazard ratio: 1.61 [95% confidence interval: 1.17 to 2.21], p = 0.004), whereas 30-day mortality was similar across quartiles of relative hs-cTnT change.
Conclusions Because stable hs-TnT levels are common in patients with a clinical diagnosis of NSTEMI in our hospital, a small hs-cTnT change may not be useful to exclude NSTEMI, particularly as these patients show both short-term and long-term mortality at least as high as patients with large changes in hs-cTnT.
This work was supported by the Swedish Cancer Society, the Swedish Research Council, the Swedish Pain Foundation, the Assar Gabrielsson Cancer Research Foundation, and by LUA/ALF Funding at Sahlgrenska University Hospital. Dr. Lindahl is a consultant or has advisory role with Philips, Biomerieux, Radiometer, Fiomi Diagnostics, and Roche. All other authors have reported they have no relationships relevant to the contents of this paper to disclose. Drs. Bjurman and Larsson contributed equally to this work.
- Received February 19, 2013.
- Revision received May 28, 2013.
- Accepted June 13, 2013.
- 2013 American College of Cardiology Foundation